The excessive consumption of sodium has adverse health effects such as hypertention. Therefore, it is mandatory to include the sodium content in the label in the US, Korea, and China. The description as to “sodium” under the basic item section is also mandated in Japan by the system of the Nutrition Labelling Standards under Article 31 of the Health Promotion Act. The measurement of sodium concentration in food products is essential and atomic absorption spectrometry is used as the analysis method. By changing the wavelength of the analytical line to the one which allows the high concentration measurement, even a solution having a concentration of several tens mg/L can be easily analyzed.
